Noncanonical NOTCH signaling limits self-renewal of human epithelial and induced pluripotent stem cells through ROCK activation

Takashi Yugawa, Koichiro Nishino, Shin Ichi Ohno, Tomomi Nakahara, Masatoshi Fujita, Naoki Goshima, Akihiro Umezawa, Tohru Kiyono

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

NOTCH plays essential roles in cell fate specification during embryonic development and in adult tissue maintenance. In keratinocytes, it is a key inducer of differentiation. ROCK, an effector of the small GTPase Rho, is also implicated in keratinocyte differentiation, and its inhibition efficiently potentiates immortalization of human keratinocytes and greatly improves survival of dissociated human pluripotent stem cells. However, the molecular basis for ROCK activation is not fully established in these contexts. Here we provide evidence that intracellular forms of NOTCH1 trigger the immediate activation of ROCK1 independent of its transcriptional activity, promoting differentiation and resulting in decreased clonogenicity of normal human keratinocytes. Knockdown of NOTCH1 abrogated ROCK1 activation and conferred sustained clonogenicity upon differentiation stimuli. Treatment with a ROCK inhibitor, Y-27632, or ROCK1 silencing substantially rescued the growth defect induced by activated NOTCH1. Furthermore, we revealed that impaired self-renewal of human induced pluripotent stem cells upon dissociation is, at least in part, attributable to NOTCH-dependent ROCK activation. Thus, the present study unveils a novel NOTCHROCK pathway critical for cellular differentiation and loss of self-renewal capacity in a subset of immature cells.

Original languageEnglish
Pages (from-to)4434-4447
Number of pages14
JournalMolecular and cellular biology
Volume33
Issue number22
DOIs
Publication statusPublished - Nov 15 2013

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Molecular Biology
  • Cell Biology

Cite this